3. Facial Pain Scale-Revised (FPS-R) "worst" low back pain rating in last 24 hours of < 3/10: Pain rating ≥ 3/10 is being used in the hopes of recruiting a group of individuals who may be representative of those likely to seek clinical services for their low back pain. Also, all FPS-Rs ("current", "best", and "worst") will be used to document the impact of treatment on self-reported pain.